The Strength of Concrete; Its Relation to the Cement Aggregates and Water - Part V

VII-GENERAL DISCUSSION.
Qualities of the Aggregates
Nothing was brought out in the tests to show marked differences in strengths because of the differences in the nature of the surface of the grains and the effect of smoothness or of differences in the porosity of the grain on the adhesion of the cement to the grain. There was some indication that the smooth and non-porous grain of the Ottawa sand gave slightly lower strength results.
J. Singleton-Green